Enhancement of migratory and aggregate activities of human peripheral blood monocyte-derived dendritic cells by stimulation with RANTES

We examined the effects of various chemokines on the functional activation of granulocyte-macrophage colony-stimulating factor (GM-CSF) plus interleuk in-4 (IL-4)-generated human peripheral blood monocyte-derived immature dend ritic cells (iDC). Stimulation of iDC with regulated on activation normal T cell expressed and secreted (RANTES) resulted in the promotion of their ch emotactic migratory capacity in response to RANTES when compared with that of unstimulated cells. TNF-alpha induced a homotypic aggregated cluster for mation of iDC in a dose-dependent manner, whereas the combination of TNF-al pha and RANTES exhibited more potent induction. IDC stimulated with RANTES were more efficient than unstimulated iDC in the production of endogenous R ANTES. Treatment of iDC with the combination of TNF-alpha and RANTES was ju st little effective for the enhancement of allogeneic T-cell stimulatory ca pacity as compared with that of TNF-alpha treated iDC. These results sugges t that endogenous secretions of RANTES from iDC stimulated with RANTES be p otentially involved in RANTES-induced changes of properties with respect to morphology and function.